The septuagint is the God-inspired version, as when paul says all scripture is God-breathed he is referring to the old testament (there was no new testament canon decided at his time) and the version he used for the old testament is this greek translation of it
As for the new testament, the church chose the canon for it, and though it wasn't fully canonised until the end of the 4th century in councils, a letter from St. Athanasius of Alexandria indicates that the orthodox canon was already established, given that the 27 books of the new testament were listed by name in the letter
For more you can look to this video https://youtu.be/Z4aqY-UdOMo
>>103623807
True